[ops-guide] Cleanup arch scaling chapter
[ops-guide] Cleanup arch scaling chapter

Change-Id: I31fc763a7b80c315b86a662cf1831fbd17e19538
Implements: blueprint ops-guide-rst

AlekhyaMallina-Vedams/openstack-manuals,openstack/openstack-manuals,AlekhyaMallina-Vedams/openstack-manuals,openstack/openstack-manuals,AlekhyaMallina-Vedams/openstack-manuals,openstack/openstack-manuals,openstack/openstack-manuals